Fast and Selective Plasmonic Serotonin Detection with Aptamer-Gold Nanoparticle Conjugates.

Neurotransmitters detection is critical to understanding communication between the brain and peripheral tissue. Serotonin is a key neurotransmitter linked to a number of conditions, but a full understanding of its role in disease is still lacking. The development of fast and selective serotonin detection platforms will provide researchers with tools to monitor serotonin in individuals before and after treatment for the condition of interest. Aptamer-gold nanoparticles conjugates that responded colorimetrically to serotonin with minimal response to its metabolite and other neurotransmitters were designed by simply adsorbing the DNA on the surface of AuNPs. A plasmonic assay for serotonin detection was designed with a response to biologically relevant serotonin levels. Importantly, the assay performance was not compromised when tested in filtered spiked fetal bovine serum as a mimic of biofluids. This work shows that these simple and stable Apt-AuNP conjugates are promising tools to develop fast assays for point-of-care and personalized diagnostics applications.